Just bought a new HD screen and now thinking of a 5.1 system for a 14' x 18' living room for music and videos.
Presently have 2 Advent 3002 (1978) speakers with the following specs: 8 inch woofer/ 1 inch dome tweeter/ 48 hz-23 khz, +-3db
88db sensitivity, @1 watt, @1 meter/ 2.8 khz crossover/ 8 ohms/ Walnut grain cabinet/ 20x12x9 inches

Thinking of getting: 2 M3's, VP 100, 2 QS4's, EP 125.
New not always being better,and outside of buying and comparing, how would the new M3's stack up against the older Advents as both having similar specs. Should I build around the Advents which still sound great?

I think you will have a kicking little set up and considering the age of the Advents, the M3's should hold their own, and then some. I own a pair and they can rock. If you like movies, you may want a little more sub than the 125 but I don't own one so who knows. I would think a 175 but probably a 350 would be best. Don't know your budget though.

I think the overwhelming opinion on these boards will be not to go for a sub under the ep350, which is a tad pricey!

Chris, welcome. Considering that the size of the 3002 has been acceptable, I'd suggest that you consider the M22s, which are slightly smaller than the 3002s, rather than the smaller M3s. A vertical M2 center(if you get a separate center speaker, rather than having the mains form a "phantom" center at first)would match well. The QS4s should be excellent. Probably a more powerful sub than the EP125 would be advisable for that room.

Of course, the size of your budget(which might be estimated from your preliminary picks)will be an important consideration.

This might be a good case for piece building the system, start with the best sub you can afford from Axiom or any place else, SVSound, Epik, Elemental Designs, etc., then add the sourrounds and center channel and finally make the upgrade for the mains. I mention these last as you say you are happy with them and are having no problems so why replace them now if you don't have to.

Thank-you for your advice.
How important is it to the sound to have the make of the center speaker and the surronds different than the mains?

Some people can't stand mismatched mains and center, others could care less as long as they have sound. The best sounding systems are all matched speakers, obviously, but the surrounds can be different from the mains and center. It is up to you whether or not you can live with mismatched sonic signatures or not. Your old speakers may work as surrounds as well, at least until you can buy some QS's, this would allow for the more critical LCR to be of the same timbre. It just gives a nicer/cleaner soundstage when the front 3 sound the same or as close as possible.

In addition to owning a pair of M3ti's I still listen to my old set of Sansui SP5500X's. They probably sound similar to your Advents so I think I have a good idea of the timbre you are used to. Going with the M3V2's and a decent sub you will sure to experience impressive midrange qualities. The M3's have an uncanny ability to be transparant combined with rich detail and retrival. The M22's are similiar but not quite as "warm". Both favor a forward presentation. It's your decision. As to a different center, I've made about three changes in the last three years and for me it has worked out fine. I won't give up my M3's for anything.

Rich (M3ti's, Aperion 5C Center, BIC V1220 Sub, Polk Surrounds)

I probably want to hold on to my Advents for sentimental reasons as I have had them for so long and because of their great bass.

But with today's materials and technology how can the M3's or M22's not be superior to such older speakers. Trying M3's with a VP100 to get the same timbre and tone seems to be the way to go. A good sub and surrounds to finish the set should than do the trick.

I would - they're an important piece of hifi history - but I'm a bit of a hoarder